It is commonly known that a voltage converting device is used in power generation for matching the variable voltage characteristics of a power source or load to the nominally fixed voltage of the grid for the purpose of supplying power to the grid from a power source or taking power from the grid to a load. Such a voltage converting device may comprise at least a voltage converting unit and at least an inter-bridge transforming unit which is adapted to operate on the voltage outputted by the voltage converting unit and to output an output voltage to the grid. Providing a plurality of voltage converting units being electrically connected to the at least one inter-bridge transforming unit or to a plurality of inter-bridge transforming units may allow for increasing the output power rating of the voltage converting device. Adding more voltage converting units may also allow an increase in the effective switching frequency seen at the grid connection point without increasing the actual switching frequency used in the voltage converting unit(s).
However, if at least one element of the group consisting of the voltage converting units and the inter-bridge transforming units fails or shows a reduced functionality, further operation of the voltage converting device may be prevented until the element may be repaired or exchanged for a new one.